KR20040083630A - A composition for print and printing process - Google Patents

Abstract

PURPOSE: A resin composition is provided to print real pictures on a metal material, which is excellent in resolution, adhesive force, and endurance and can shorten a printing process. A printing method using the resin composition is also provided. CONSTITUTION: The resin composition comprises 40-70wt% of at least one resin selected from an acryl resin, a polyurethane resin, a polyvinyl alcohol resin, an epoxy resin having a solid component of 20-50%, 20-50wt% of a diluent, 3-20wt% of silica, 0.05-1wt% of a humectant, and 0.01-30wt% of a curing agent and has a viscosity of 200-400cps. And the printing method comprises the steps of: removing extraneous matters from the surface of the metal material; base coating the resin composition to a thickness of 3-50 micrometer and then drying; printing real pictures by using an aqueous ink and then drying; top coating a UV-screening resin to become a thickness of 1-50 micrometer and then drying.

Description

Photorealistic printing resin composition for metallic adherends and printing method using same {A composition for print and printing process}

The present invention relates to a resin composition and a printing method applicable to printing on a metal adherend such as a metal plate, and more particularly, to a metal surface while printing and printing by directly printing on the surface of the metallic adherend without using a transfer method. It is to provide a low-cost printing resin composition and a printing method using the same, which is excellent in adhesion and durability and excellent resolution and can deliver a realistic image as it is.

In general, printing can be classified into light printing and special printing according to the type of adherend. Light printing refers to a method of realizing a specific image on paper, and special printing refers to a method other than paper such as silk screen, actual printing, and transfer printing. Refers to implementing a specific image on the adherend.

Transfer printing during special printing refers to a method of printing a specific image to be implemented on a special paper for transfer paper first, then attaching it to the adherend, and then heating it to end printing. The special paper used as a transfer paper is mainly chrome. Laminates, such as paper, china paper, and laminated double or multi-laminated paper, and those coated with polyvinyl-based resin on it are used. Sublimation dyes are printed on it.

Conventionally, in order to realize an image on a metal-like adherend, a printing method using a transfer paper has been common. Thermal transfer (heat bonding) is performed by applying a high heat of 150 to 250 ° C. after printing a print using a sublimation dye on a separate transfer paper. Then, a method of coating the sunscreen was adopted to improve the durability of the printed image thereon. However, the sublimation dye itself is vulnerable to UV rays, and thus has a low blocking effect even when applied with a UV blocking coating. Also, the thermal transfer method has a low resolution, which is not suitable for printing requiring high-precision patterns such as advertisements, but also at high temperatures. There was a problem in repeatedly implementing the same color by changing the color of the printed image due to a slight temperature change during the heat treatment process.

In addition, by adding a job to first print the image to be implemented on the transfer paper, the work efficiency is lowered, the cost is added, there is a disadvantage that productivity and marketability is lowered.

As another method to supplement this point, a method of performing live-printing on a metallic adherend directly without using a transfer paper has been proposed, and a method using a resin capable of UV curing. However, this method is not only expensive due to the specificity of the resin, but also lower than the conventional transfer method, the resolution is as high as 720dpi, the final printed surface is rough, and the adhesive strength is less than 7kgf / ㎠, and thus the bending of the metal plate after printing There is a problem in that the printing of the bent portion is peeled off when performing the molding process.

As another method, a solvent-based resin composition mainly based on a solvent-based resin, and a solvent-based and UV-curing agent are mixed and applied. However, this product is also low in adhesive strength and low resolution in order to be expensive. There is an inadequate problem.

The present invention has been made to solve the above-mentioned conventional problems, it is possible to directly print due to the metallic adherend without using a transfer paper, it is not only suitable for the printing of advertisements that require a high-resolution reproduction of the sophisticated image It is to provide a printing resin composition which is excellent in adhesive strength and durability and which does no harm to the printing site even when molded into any form such as bending a metal sheet.

Still another object of the present invention is to provide a live-printing method on a metallic adherend using the printing resin composition according to the present invention.

The present invention 40 to 70% by weight of at least one resin selected from acrylic, polyurethane, polyvinyl alcohol, epoxy resin of 20 to 50% solids, 20 to 50% by weight of diluent, 3 to 20% by weight of silica, wetting agent The present invention relates to a live-print printing resin composition for metallic adherends comprising 0.05 to 1 wt% and 0.01 to 30 wt% of a curing agent.

Hereinafter, the present invention will be described in more detail.

[Resin Composition for Printing]

The resin according to the present invention preferably has a solid content of 20 to 50% and at least one selected from acrylic, polyurethane, polyvinyl alcohol, and epoxy resins, and the content of the resin is 40 to 70 in the entire composition. Preference is given to using by weight. In the composition of the present invention, when selecting two or more resins, the content of each resin is mixed in the range of 10 to 40% by weight, but the total content may not be less than 40% or more than 70% by weight. .

Solid content of the resin constituting the resin composition according to the present invention is preferably 20 to 50%, but less than 20%, the viscosity of the composition is lowered, it is difficult to form a coating film when applied to a metal adherend before actual printing, drying, etc. In case of exceeding 50%, the viscosity becomes high, and the spray gun or the like cannot be used in the method of forming the coating film, and the agglomeration and partial solidification of the resin solution occur, which is not preferable.

In addition, when the content of the resin in the present invention is out of the range of 40 to 70% by weight presented in the present invention, it is difficult to maintain the viscosity of the resin composition, and there is a disadvantage in that the adhesive strength and resolution are inferior.

The diluent used in the present invention may be methyl alcohol, isopropyl alcohol, ethyl acetate, toluene, or the like for improving coating performance and drying properties by adjusting viscosity. In addition, this can also be used individually by 1 type or in mixture of 2 types of mixtures, or all 3 types of mixtures in the same system.

The content of the diluent according to the present invention is preferably 20 to 50% by weight. If the amount of the diluent is less than 20% by weight, the difficulty of dilution of the resin composition, which is a basic performance as a diluent, may cause coating performance and dryness to improve viscosity and printability. When it exceeds 50% by weight, the solubility and viscosity are not only poor, but also the adhesive strength to be achieved in the present invention cannot be achieved.

Silica used in the present invention is used to improve the printability, the average particle diameter of the silica used is preferably 1 to 50㎛, the content is preferably 3 to 20% by weight.

If the average particle size of silica is less than 1 μm, the cost may increase due to the continuous grinding of the particles, but the printability may be reduced. If the average particle diameter is more than 50 μm, the particles become larger and the surface becomes rough after application and the gloss is lost. It is undesirable because matting and peeling of the silica itself may occur.

If the content of silica is less than 3% by weight, the printability is lowered, which is not preferable. If the content of the silica is more than 20% by weight, the excessive content of silica may cause problems such as peeling and gloss reduction and reduction of printability.

The wetting agent used in the present invention is used for the purpose of bubble prevention and adhesion enhancement, and is preferably 0.05 to 1% by weight using polyethylene glycol or the like. If the content of the humectant is out of the range proposed in the present invention, the wetting function such as bubble prevention is lowered, which is not preferable because the printability and adhesiveness are lowered.

As the curing agent used in the present invention, isocyanate, melamine formaldehyde, polyamideamine, polyamideamine, etc. may be used, and a range of 0.01 to 30% by weight is preferable. When the content of the curing agent is less than 0.01% by weight, the curing is not performed properly, the adhesiveness is lowered, and when the content of the curing agent exceeds 30% by weight, there is a problem that the printability due to the imbalance of viscosity, instability due to excessive curing occurs.

Each component according to the present invention is mixed and then stirred for at least 3 hours for uniform dispersion to obtain a uniform composition having a viscosity in the range of 200 centipoase (cps) to 400 centipoase.

[How to print]

First, in order to obtain a uniform printing effect on the adherend, after preparing a metallic adherend from which the contaminants on the surface have been removed, the resin composition according to the present invention may have a thickness of about 3 to 50 μm in order to maintain stable adhesion of the actual printing ink. Primary coating treatment uniformly, commonly referred to as 'undercoat'. Undercoat treatment can be cured by natural drying, but when rapid drying is required, it is dried for 10 to 300 seconds on the basis of 2m2 at a temperature of 110 to 190 ° C by applying a thermosetting method. When the thickness of the undercoat is less than 3 μm, the excellent adhesive strength and high resolution of the resin composition according to the present invention cannot be maintained. When the thickness of the undercoat exceeds 50 μm, peeling of itself occurs rather than the purpose of the present invention. You can't achieve it. When the undercoat is dried by thermosetting instead of natural drying, when the temperature exceeds 190 ° C., discoloration (yellowing) of the resin composition and the coating film may be dissolved, which is not preferable.

As the metal plate to which the resin composition according to the present invention may be applied, iron plate, stainless steel, copper plate, or other metal plate may be applied. In some cases, various materials such as non-metal plate such as plywood, acrylic plate, and glass may be applied. Do. However, most preferably, it is a metallic plate material.

After the drying of the roadway, due diligence printing is carried out using a plotter. The live printing ink can be classified into water-based ink, oil-based ink, and UV-curable ink. Among the water-based ink, there are water-based pigments that are resistant to ultraviolet rays and water-based dyes that are resistant to ultraviolet rays, and aqueous pigments resistant to ultraviolet rays are preferable.

In addition, oil-based ink has oil-based oil and solvent-based, but when the solvent-based is used, the bonding strength is stronger due to the chemical bonding with the channel with the present invention. The disadvantage is the high cost of the ink.

UV-curable ink is a mixture of UV-curable ink and adhesive resin, which is expensive. It is a quick-drying ink by UV light, which is extremely weak in printability and adhesion. impossible. Therefore, in the present invention, ink using an aqueous pigment is preferable for the intermediate treatment.

After the end of the intermediate treatment heat or natural drying at the same temperature as the undercoat treatment to protect the printed surface of the UV protection resin to a thickness of 1 to 50㎛ and this is called 'top treatment'. Drying after the top coat may be natural drying or heat drying and is not particularly limited for the present invention.

The printing method using the resin composition for live-action printing according to the present invention can be applied by integrating the order of the bottom coat, the middle coat and the top coat in order to shorten the printing process and reduce the cost. In this case, the mixing ratio of the top coat and the bottom coat is 40-80: 20-. It can mix and use in the ratio of 60.

Furthermore, the printing method using the resin composition for live-action printing according to the present invention can be applied by unifying the degree, the middle and the top coat, in this case, first adjusting the ICC Profile (plotter printing amount adjusting device), but the degree of the middle, middle and top coat The mixing ratio may be mixed at a ratio of 30 to 70: 20 to 60: 10 to 40, and then stirred for at least 3 hours to form a homogeneous system, which may be printed and thermally dried by a direct injection method.

Hereinafter, the present invention will be described in more detail by way of examples, but modifications are possible within the scope of the present invention, and the present invention is not limited by the following examples.

<Example 1>

[Resin composition manufacture]

30% by weight of polyurethane resin with 35% solids and 30% by weight of acrylic resin with 35% solids, 34.67% by weight of 1: 1 mixed solution of methyl alcohol and isopropyl alcohol, 5% by weight of silica with an average particle diameter of 3 to 8 μm, polyethylene 0.3% by weight of glycol and 0.03% by weight of melamine formaldehyde were added to the mixture, and the mixture was sufficiently stirred for 5 hours to obtain a viscosity of 270 centipoase (cps).

[Metal deposit preparation]

Iron plate was selected to clean the surface of contaminants to remove foreign substances from the plate.

[print]

The printed resin composition prepared by spraying the surface of the plate material from which the foreign material was removed is sprayed. During the undercoating, the coating thickness was 6 μm and then dried at 150 ° C. for 90 seconds. Immediately after drying, real-life printing is performed with an aqueous ink using a plotter, followed by heat drying at 150 ° C. for 20 seconds. Finally, the sunscreen solution was applied to the dried surface with a thickness of 7 μm, and after the top coat was heat dried at 150 ° C. for 90 seconds and packaged with a protective film to complete the product.

<Example 2>

Polyurethane resin 30% by weight 40% solids 32% by weight acrylic resin 40% solids, 19.5: 1 mixture of methyl alcohol and isopropyl alcohol as diluent 29.5% by weight, silica 3 A resin composition was prepared to make a uniform system by adding 5% by weight, 0.4% by weight of polyethylene glycol as a humectant, and 0.1% by weight of a curing agent melamine formaldehyde resin, to prepare a uniform system with a sufficient stirring for 5 hours, and to have a viscosity of 260 centipoase (cps) The same process as in Example 1 was applied except that this was applied to the copper plate.

<Example 3>

30% by weight of polyurethane resin with 30% solids and 30% by weight of acrylic resin with 30% solids, 30.7% by weight of 1: 1 mixed solution of methyl alcohol and isopropyl alcohol as diluent, silica with an average particle size of 3 to 8 µm 9% by weight, 0.2% by weight of polyethylene glycol wetting agent, 0.1% by weight of curing agent melamine formaldehyde resin was sufficiently stirred for 5 hours, except that a resin composition of viscosity 280 centipoase was prepared and then applied to an aluminum plate. It carried out by the same method as Example 1.

<Example 4>

25% by weight of polyurethane resin with 35% solids and 35% by weight of acrylic resin with 35% solids, 33% by weight of 1: 1 mixed solution of methyl alcohol and isopropyl alcohol as diluent, silica with an average particle size of 3 to 8㎛ Except that 6.7% by weight, 0.23% by weight of polyethylene glycol wetting agent, 0.07% by weight of curing agent melamine formaldehyde resin was sufficiently stirred for 5 hours, a resin composition of viscosity 290 centipoase was applied and then applied to a glass plate. It carried out by the same method as 1.

<Comparative Example 1>

The final product was completed after printing on the metal surface using the ultraviolet curable resin conventionally sold.

<Comparative Example 2>

The final product was completed after printing on the metal surface using a transfer paper conventionally sold.

As a result of measuring the adhesion strength and bending test and the resolution of the actual printed surface obtained in Examples 1 to 4, in Examples 1 to 4 according to the present invention, the adhesive strength was 90% in primary and 85% in secondary. On the other hand, the third 90%, the fourth 90%, the fifth 95% to represent an average of 90%, that is, 15 to 25kgf / ㎠, while the comparative example was only 5 to 10kgf / ㎠. In addition, in the bending test, in Examples 1 to 3 according to the present invention, each of the bending was performed 10 times at 90 degrees and 360 degrees, but peeling of the printing surface did not occur, but Comparative Example 1 was completely peeled off, and Comparative Example 2 was Partial peeling occurred.

The resolution of the photorealistic printing surface of the present invention was 1,440 to 2,880 dpi, indicating that it was superior to Comparative Example 1, which was only about 720 dpi.

<Property measurement method>

1) Adhesive strength (kgf / ㎠): Apply cross-hatch, make a scale with a blade and cut it.

2) Bending test (number of times): When the sheet metal was folded at 90 degrees and 360 degrees, the degree of bending of the printed portion was measured visually.

3) Resolution (dpi): Dots per inch

As described above, the resin composition for live-print printing according to the present invention can be directly printed on the surface of the metallic adherent, not the transfer method, but has excellent adhesive strength and resolution, and can be molded into any shape while maintaining the actual image as it is. It can have an effect that can be implemented.

In addition, it is also possible to use a single resin by mixing a water treatment and a low-cost water-based printing ink for the actual printing and lower cost, it also has the effect of shortening the production process while reducing the cost.

Claims (10)

40 to 70% by weight of at least one resin selected from acrylic, polyurethane, polyvinyl alcohol and epoxy resins with 20 to 50% solids, 20 to 50% by weight diluent, 3 to 20% by weight print wetting agent, and wetting agent 0.05 To 1% by weight and comprising a 0.01 to 30% by weight of the curing agent and having a viscosity range of 200 to 400 centipoase (cps), a live-print printing resin composition for metallic adherends. The method of claim 1, wherein when the resin is two or more, each resin is mixed in the range of 10 to 40% by weight, characterized in that 40 to 70% by weight in total, the live-print printing resin composition for metallic adherends. The diluent of claim 1, wherein the diluent is at least one member selected from methyl alcohol, isopropyl alcohol, ethyl acetate, toluene and toluene. Printing resin composition. The real-life printing resin composition for metallic adherends according to claim 1, wherein the printing agent is a silica powder having an average particle diameter of 1 to 50 µm. The live-printing resin composition for metallic adherends according to claim 1, wherein the humectant is polyethylene glycol. The real-life printing resin composition for metallic adherends according to claim 1, wherein the curing agent is melamine formaldehyde-based or isocyanate-based or polyamideamine-based. Selecting a metallic deposit to remove foreign matter from the surface; 40 to 70% by weight of at least one resin selected from acrylic, polyurethane, polyvinyl alcohol and epoxy resins with 20 to 50% solids, 20 to 50% by weight diluent, 3 to 20% by weight print wetting agent, and wetting agent 0.05 To 1% by weight and 0.01 to 30% by weight of the curing agent and after the bottom coating treatment of the actual resin printing resin composition for metallic substrates having a viscosity range of 200 to 400 centipoase (cps) to a thickness of 3 to 50㎛ Drying; Real-life printing using an aqueous ink and then drying; A method of printing using a live-printing resin composition for metallic adherends, comprising: drying the UV-blocking resin to a thickness of 1 to 50 μm and then drying. The method of claim 7, wherein the drying method after the undercoating treatment, the actual printing and the top coat treatment is natural drying or drying for 10 to 300 seconds at 110 to 190 ° C. . 8. The live-printing resin composition for metallic adherends according to claim 7, wherein the resin for top coat and the top coat can be mixed and printed in one step, and the mixing ratio is 40 to 80:20 to 60. Printing method using. 8. The resin according to claim 7, wherein the resin for undercoating, live-printing and topcoat can be mixed and printed in one step, and the mixing ratio is 30 to 70: 20 to 60: 10 to 40. Printing method using a live-print resin composition for adherends.